$ { \left[\begin{array}{rrr}{3} & {4} & {-1} \\ {-1} & {1} & {-2}\end{array}\right]-\left[\begin{array}{rrr}{3} & {-2} & {4} \\ {2} & {-2} & {-1}\end{array}\right] = {?} } $
Explanation: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{3}-{3} & {4}-{-2} & {-1}-{4} \\ {-1}-{2} & {1}-{-2} & {-2}-{-1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{0} & {6} & {-5} \\ {-3} & {3} & {-1}\end{array}\right]}$